The Process and Challenges of Email Delivery

Email delivery is not as simple as it seems. It involves two servers that communicate with each other to send and receive emails. Each email has a header and a body. The header contains information such as the sender’s and recipient’s addresses, the subject line, and the character encoding. The body contains the actual message.

The sending server uses the Domain Name System (DNS) to find the recipient’s server address by breaking down the email address into its components. The DNS also tells the sending server if the recipient’s domain exists and which server is responsible for its mail.

The sending server then tries to deliver the email to the recipient’s server by “shaking hands” and “greeting each other”. However, there are some factors that can prevent or delay email delivery, such as:

• Permission: The sending server needs to have permission to deliver the email to the recipient. Some servers may require authentication or encryption to accept emails.
• Spam filters: The recipient’s server may have spam filters that block or divert emails that look suspicious or unwanted. Spam filters use various criteria to identify spam, such as keywords, sender reputation, attachments, etc.
• Server capacity: The recipient’s server may be overloaded or offline due to high traffic or technical issues. In that case, the sending server may retry delivery later or return the email with an error message.

Therefore, email delivery is not always instantaneous or guaranteed. It depends on the interaction between two servers and their ability to overcome potential obstacles.